Process of treating ores.



E. H. SNYDER.

PROCESS 0F TREATING ORES. APPLzcATloNflLED MAR. si. 915.

Ground ore, we me sh Roasted ove mostly as Treat with Hot HzoJfHqsonNazSOA Mq, wat ath zin.:

to ppt cu.

Snhdinn 'Zm S04 (f msm) *produce solution 'Ln S01; l

Nm 5011 Sol.

Patented May 23, 1916.

Mau mid Cum 'lm k VPL A9 Raus( wl l: h

Cmrbun Solution l Pe (o H )a witness@ Athi H1504 in head! hemlmd or mid H10 'to prt 'ZmQOQ Ba. CO

'Tveu-t with Nnlson SQL E .H Snyder'. Inventor Cllioznm,

Bewaren nanmson summa, or moons, NEVADA..

PROCESS .0F TREATING GRES.

1,184,585. i l y Application tiled March 3 To alltelwmz'mai/f concern: I

Be itknown thatl, EDWARD H. SNYDER, a@ citizen :of the United States, residing at -1 Pioclie, the4 county of zfofNeyadayhaie :invented new and useful 1 Improvements inl Processes of Treating ".OresVof whichthe following is a specifica- "tionr "l The present Vinyention. relates to the treatmentot complex ores, such as ores containing zine `and lead, with or without other u .metals, such as copper, iromsilvengold or others, and isapplieable whether the metals Nexistin the` ore `principally as sulfids, or y principallyinother forms, such as oxld or carbonate', or mixtures thereof.

s lrssuming` that the ore being treated is an ore in which sulfids predominate, the ore is "irstground, preferably to pass a one hun- 1 dred mesh sieve, and is then roasted in order "to convert themetals into oxid, and to drive `ott" the sulfuriin the form of sulfur dioxid "which may be converted into sulfuric acid y f fg j .for Vuse in the process, in any suitable man- 25 ner. v

l 1 ln thetreatment of certain classes of ore, 'i lit isfadvisable before grinding to add a small amount of sodium sulfate, or other alkali f metal.sulfate` beforel roasting,` otherwise a portionoft the Y," :will notbe .leachable. The accompanying drawing shows a dia- Ugram of the process, andis not intended toillustrate any particular `apparatus used fini carrying out the process.

ln saidadrawing, l representslthe step of "roastingthe ore, and 2 the suli'uric acid plant` The roasted ore is carried to a suitable pvat illustrated at ffl, in which it is treated with a `solution containingr sodium sulfate, a .fsmallxaniount ot' sulfuric acid, and a. conisiderablewanmunt ot' water, the treatment `being etlected in a heated condition. ',lhe l solutionlmay bepassed through a tank l I"feontail, 'iig `suspended pieces ot coppcror \i"f;inc,`to` precipitate the silver.` which is 'thereby; removedfroin the, solution and recovered; r`he"`liquid then `passes to tank 5, in which itxisitreated with caiuistie soda solution, in sliglit Yeiicess .only7 in order to precipitate zincliydroxid,i` which if substantially free from ironandcopper may be calcined and sold' aslzincoiiid1 or if this `zinc hydroxid Specication of Letters Patent.

' described. Lincoln and State 'w ith waste gases7 from the 'solution will preferably be Patented May 23, 1916.

1,1915. Seri1N0. 18,355.

amount of iron or it may be purified as hereinafter The waste liquor,v which consists essentially of .a solution otsodium sulfate may be returned to treating vat 3, and this cycle ofoperationsmay be repeated until the solution accumulates a considerable amount of sodium sulfate, when it will be transferred to tlieyat v(i, and treated with contains a considerable copper,

either barium or strontium hydroxid to produce causticsoda which may be used in the various steps of the process. The alkaline earth sulfate obtained here is then roasted with carbon and converted into sulfid. This sultid is dissolved in a small amount of water and-the solution treated various furnaces,

containing carbon dioxid. By this means v,the alkalineearth sulfid is changed to carbonate and the hydrogen sullid toi-med at the same time can be saved, and used for making sultur dioxid for the sulfuric acid` plant. The alkaline earth'carbonate is separated 'from the solution and takento a suitable turnaceand calcined yto produce line earth oxid for use 4in vat (3. When barium is the alkaline earth used, the fine precipitated carbonate from the above opel ation is agitated with a hot solution'of so dium sulfate., thereby changing the barium carbonate to `barium sulfate, same time producing sodium carbonate in solution, which is filtered oil' and treated with quick lime to form sodium hydroxid.

rlhe ore from the vat vat 7, wherein it is treated with a strong solution of caustic soda, say three to ten per cent. strength, which solution will be maintained near the boiling point, it the ore contains copper, in` order to prevent the copper from entering the solution. If the ore is substantially tree from copper, the employed cold, since zinc will be less soluble in the liquor il' hot, than it` cold. ln this vat, I vmay also employ zinc plates, to precipitate any dissolved lead, (which would be in the form of sodium plumbate'), thereby removing the lead from the solution, and` also recovering the lead in metallic form as a product. r`he solut.on containing sodiuml zincate, caustic soda and `usually also sodium plumbate, is conveyed to the tank 8, wherein it and at the ni .fitnessen is partly neutralized with sulfuric jucid, .other@cielmore'electieocsitive than solo? leaving;r the solution slightlynllmline,perf tiiiih e'coppen'citer this treatment, zinc hydroxidlead h s ciidlliqiicrs willige' onveyed tothe;v and leed sulfate will be precinitete, will" i te'tlie'tenir c l may be purified and separated es dest-.ri I

below. Liquor from tank 2 muy be d,

.- I v 'j 'niinedwitiiecdiuni"self As an alternative step at this vint, I 'clinsfat/ send roested'in'tlie rocstei il, and then' convey the solution from the tan l into the y*conveyecl tortenkf, where it is treated iii` f tank 9, where the solutionwill be slight] substantially theffssine manner 'es kabove 75 acidiliel with sulfuric acid to precipitate a l specified, 1"'1- l u lead as sulfate, and to form zinc sulfate Inoideiteinelxenp fcrthe'less dnredinin solution. Thezinc lsulifnte solution will ,be sulfetegia'sniall emonnte thelsuiurieecid' conveyed tothe tank 10 1and may he made `'will A pre:ierelilyhe -isedfc'fe i'jtreetincnt slightly alkaline-with caustic soda to pif@ of sodium chlorid intliefsuliste inrn'iioe i9, cipitate zinc hydroxid. This zinc hydroxld ythereby producing hydrcciilcrie'ncid es e will Aordinajrilyh'e pure, and can be celcmed lay-product and producing sodium sulfate directly to forni zinc oxid.. y If desired, and which iney he used in 'the roasting cpere-- if the zinc hydroiiol he notsuiciently pure, tion, mixed with, the ore, or .inc he used in 2o-t cfm QiXS Pliffd 11S deslbed be1DW-' any of the steps in which so icm snlfcte is The ore from the alkaline' treatment in is empiyo v v tank -7 iS COHV/'ed' i0 th tank 11, Where l? Snif-uric :acid iroin the plant 2 is used in S treated Wllll sulfuric 'lCltl lll EXCESS, t0 ihn, minimis gpemigns in maks 39 S9 5);, 1li dissolve zinc, copper, sind some iron. The and 1e y l I 26 liquor from this treatment may be conveyed 'lfVhile I have referred throughout the en to the tank l2, where it is treated With COP- specificntion to the use of sodium sulfate y per to precipitate any Silver Whdh muy be and causticj sode, as the reagents to be ern dissolved in the treatment in tank 1l, after poyed, I will' Stare has my gehe; alkali which it is wmeycfi t0 the tank 13 (01' ill@ sulfate und cnustic nlknli may he used, such 8c liquor may be conveyed directly from tank as potassium sulfate and caustic potnsli.- en 11 to tank 13, in ense it does not contain l desire to call attention to the factjthst any material nmounts of silver). Irrthe the ore after treatment with [acid is more tank 13 the solution is treated with 11'011 readily attacked by allnilinesolntions than or zinc to precipitntethc copper, which is would he the ore before such treatment with thereby recoyered. The solution from tank ncid. I also desire to .call attention to the lo@ 13 is conveyed to the teni; 14, where 1t 1s fact that the ore after the treatment with 'treated with caustic sode in Slight eXCeSS, alkali is more readily attacked by acids than i" to precipitate zinc .hydroxid und iron l1ybefore the treatment,

droxid. The residue from tank 1l being lt is to be noted that zinc is soluble either 4 impure (and else the zinc hydroxid obin a strong alkali or in an acid; lead hy ice tained in certain of the previous steps, 1f droxi'd is soluble in a strong alkali, but is impure) will be conveyed to tank Where Anot readily soluble in sulfuric ucid of low it 1s treated with strong caustic socia to d1s -concentration, since leed sulfate is precipisolvethe zinc as sodium zincato, and the tated from its solutiony in concentrated sul 46. viron hydroxid remains undissolved and is furie acid, eitherA by dilution, or by neuil@ thereby seperated from the zinc. The solu.- tralizing the acid. tion of sodium zincate from tank 15 will he Copper is solnhieA in neid sclutions, but

'conveyed to trink 1G, where it is treated with not to any considerable extentein hot el 1 sulfuric acid, nearly to neutralization, or kaline solutions. Metellic copper will pre1' Nuis diluted with water, either of which will cipitate metallic sliver/:troni solutions conf'lw i cause the precipitution of zinc hydroxid in taining silver sulfate. Metellic zinc 'will ya. pure' condition'wliichinsy be celcined to precipitate either lead, copper-or silver from produce zinejoxid. v I kits solutions. -Metcllic iron will precipitate he sodimneulcte solutions from 'tanks either silvez` or cop i' fromits'solntimns.,1y 10, 14,'und l16, may he conveyed to the tank -While I have escribed the particular 12@ v 6, for ceusticization. Y 'treatments of theweiions liquors, l do not The liquors :from tank 3vu{lproduced'uby limit myself to thes'eimcttreatnients, sincev the leaching ofthe roastoreWi-thsodiuxn other methods ofprecipitiitingitlfe metals- 'sulfate, sulfuric acid en@ water, 'asabove4 'from solutions, in some-ceses, may be ein-" "more fully described) may contain more plo ed. 1 Q y 125 crises silver, in Which cese "hey may he Yliile l have described 'a particular treated intsnlif 20 with copfner o1."A oth., method of purifying the' zinchydroiiid, I metal more' electro-positive than silver," fo' don'ot desire'to limit myself to this particu# y precipitate the silizcrinn metallic condition, vliu method,A since other` methods of accom-f' and they may then' be .treated with eine, or; l@ilishingg' vthisresluflt Inlay be employed, `l 13o [The residual or after leaving the tank All;` may still ycontain a considerable amount p Qofftlie` silver originally cntained in this ore,

gundf alsoiiwill; contain'` substantially all of thefgoldloriginally contained in the ore.

v Havingnthus fully described my invenmay lead i jjj `tion, what I claimas new and desire to se- )it cure byLettersPatent, isz- K i l process oftr'eati'ng oxidized ores containingflead,zinc and other metals, i hiclrconiprises leaching the oxidized ore wwitlia hotiliquid containing an alkali sul fate, `andcontaining sulfuric acid 1n amoun ,i suiici lnttodssolve a part only of the zinc y contained in said ore,`separating the resulting liquid from `the ore, and rendering the i i t i1 same? slightly` alkaline to precipitate zinc ll25liy `.lroxid, `treating the digested ore with a l strong solutionlof caustic alkali to` extract i ,1 la further amount of zinc from the ore, an

`addiiig tothe lliquorthereby produced, an acidi in` amount at least nearly equivalent i tothe alkali` present in said solution, to `precipitate leadl` therefrom. l K l illprocessof extracting lead and zinc from ores containing these and other metals Iwhich 1 comprises `first roasting the ore, treatingtlie same with a hott liquor containing a elatively small amount of a free sulfuric i acidfand containing an alkali sulfateytreatlyinggthe liquor y thereby obtained with a i`ijr`ietul` to precipitate metallic silver, tr'eat- `iiigvj tho rcsulti'ngliquid with caustic alkali Dto fprecipitate zinc iesulting liquidto sulfuric acid, for again extracting roasted ore, and repeating this fcycleoffoperationsuntil a solution containingfconsiderable amounts of alkali sulfate `(produced,` and then causticizing said alkali sulfate solution.

43. A ,process of `extracting values from complex aulfid ores, w'iiich comprises roasty ingjtlie crushed ores with an alkali sulfate; l lleachingfthe roasted ores with a liquid conltaining "sulfuric acid; and alkaliv sulfate; i treating `theliquid thereby produced with afmetal i to precipitate` silver, yvth an; alkali to precipitate zinc, treating the partly extracted ore with a strongsolugtionof caustic alkali, and recovering zinc i, anilflead `froniysaid liquor, further treating l" the `ores` with sulfuric acid to dissolve cop- 4 4ptn.` and glzinc, said solution by treatment with a metal more j; y electro-positive ,than` copper, `precipitating zinchydroxid "from said liquor, purifying kthef,fsamo,Hand` calcining to produce zinc These metals" maybe `recovered from thel "Theniixture ofllead sulfate, lead hythis y flux,

furic acid, leaching hydroxid, addingI the f leaching the ore and thereafter` precipitating copper from'` 4. A process of treating complex ores which-comprises roasting. said ores with small amounts of an alkali sulfate to produce oxidized ores, treating said ores with a liquor containing sulfuric acid, `and separating the solution therefrom,A then treating said ores with a solution containing a considerable amount of `caustic alkali, and separating said liquor therefrom, then treating said ores with a liquor fcontaining sulfuric acid, and separating said liquor therefrom, and recoveri by each of said liquors.

ng the metals extracted,

A process of separating `metals "from l.

complex suld ores, which comprises roasting said ores with` a small Lamount of a oxidizing the SO2 given od to sulthe roasted ores with a' hot liquor containing sulfuric acid and an alkalisulfate, precipitating silver from the solution by treating metal, treat-ing the resulting liquor with caustic alkali in slight excessto precipitate zinc, treat-ing the residual ores with strong caustic alkali solution to dissolve a portion of the zinc, and substantially all the lead, slightly acidulating the solution with sulfurie acid to precipitate leadisulfate, and treating the remaining solution with caustic alkali to precipitate zinc, further extracting the ofreswith sulfuric acidto dissolve copper and zinc, treating the liquor thus produced with zinc to precipitate copper, adding caustic alkali to'tlie remaining liquor to precipitate zinc and iron hydroxide, dissolving tlie zinc hydroxid in caustic alkali,

amount of free sulfuric acid, leaching with a solution containing caustic alkali, again leaching w'ith sulfuric acijd of a strength considerably greater than that employed in the iirst leaching step, and recoveringinetal values from the three liquors. y

7 A process of treating complex orles which comprises roasting, the ore with a small amount of an alkalijsulfate, leaching the ore with a weakly acid` solution, leachingthe ore with an alkaline solution, again with an acid solution of materially greater ployed in the first leaching step, and recoyering metal values from the three liquors.

8.v A process 'of treating complex ores which comprises roasting the ores, treating with a liquor containing a relatively Vsmall amount of sulfuric vacid to extract zinc from the.ore,and recovering zinc from the leaching solution; treating thel residual ore a further amount of zinc,

the same with a` acidity than' that ein! mmm@ A zinxrfrom the leaching. solution; zegtng En esmaoqywhezjwjf v n ytgh@ @Witze leaehed. or@ with lsulflmoam Qi `my hand m presen@ "of tw@ subscmbmg hs hreufnto set www .'SNYDER. 

